System for a Retrofit Trigger Actuating Mechanism Integrated Into a Semi-Automatic Rifle

ABSTRACT

The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle alters the dynamics of the firearm and allows for a higher firing rate. More specifically, the retrofit apparatus divides the semi-automatic rifle into two regions that are slidably coupled and thus allowing for the user to utilize a bump fire technique. The relative motion of the two regions allows for the trigger to be pulled, re-set, and pulled once again in a sequential manner yielding a higher firing rate when compared to standard semi-automatic rifles. During the sequential firing the user keeps the firing finger in a set position without any movement; the trigger is pushed into the finger to initiate the firing sequence each time. The components of this system do not require modifications for the rifle and may be integrated quickly and easily.

FIELD OF THE INVENTION

The present invention relates generally to firearms. More specifically, the present invention is a retrofit kit for semi-automatic rifles that allows the user to increase the firing rate by utilizing a controlled bump fire method.

BACKGROUND OF THE INVENTION

A firearm is a small arms weapon which is capable of accelerating a relatively small projectile to substantially high speeds through the use of gunpowder and other similarly explosive material. Firearms include, but are not limited to, handguns, shotguns, rifles, carbines, machine guns, and submachine guns. There are three main categories which categorize fire arm single shot, semi-automatic, and automatic. A single shot firearm can only be fired a single time; this requires the user to reload the gun each time the gun is fired. A semi-automatic, also known as self-loading, firearm is a weapon that automatically executes all the necessary functions required for successive firing; incremental round discharge with the user pulling the trigger for each round. Functions include retrieving and ejecting the previous cartridge in the chamber, resetting the firing mechanism, and loading the next round into the chamber. The majority of basic firearms require the user to perform at least one of those functions manually after each shot resulting in a time lag between shots, a substantial disadvantage in life threatening situations and or when compared to alternative firearms. Full automatic firearms are, by definition, the fastest and most efficient guns in the field but they are accompanied by a plurality of government restrictions as well as an extremely high price tag; this type of firearm performs all the necessary functions for continuous firing as long as the trigger is depressed.

Compared to the automatic firearm, the semi-automatic is generally lower in cost and has looser restrictions and thus has been the base for modifications and alterations. Different means have been invented to attempt to increase the firing rate of a semi-automatic, but each solution is accompanied by a significant compromise such as increased recoil and or lower accuracy.

The present invention provides a retrofit kit which increases the firing rate of a semi-automatic firearm. The retrofit kit increases the firing rate of a firearm through a method called bump fire; the method utilizes the recoil of the previous shot in conjunction with a forward pushing motion of the user's hand to re-set and activate the trigger in a smooth quick sequential manner yielding a faster firing rate. While similar alternative means fully modify and change the actual firearm, the present invention is a simple addition that is compatible with standard stock and lower receiver designs. The components are easily to install and remove resulting in a superior product.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is perspective view of the present invention.

FIG. 2 is an exploded perspective view of the present invention.

FIG. 3 is an exploded perspective view of the present invention, depicting the connection between the lever arm and the stock components.

FIG. 4 is a right-side view of the present invention after a round discharge; the arrow conveys the direction of the force due to recoil.

FIG. 5 is a right-side view of the present invention, the arrow conveys the direction of the force due to the user pushing forward to reveal the trigger and initiate another firing sequence.

FIG. 6 is a perspective view of the retrofit actuating mechanism.

FIG. 7 is an exploded view of the retrofit actuating mechanism.

FIG. 8 is a perspective view of the upper guide bracket.

FIG. 9 is a top perspective view of the lower finger guide bracket.

FIG. 10 is a bottom perspective view of the lower finger guide bracket.

FIG. 11 is an alternative perspective view of the present invention depicting the various components of the semi-automatic rifle, especially the lower receiver.

DETAIL DESCRIPTIONS OF THE INVENTION

All illustrations of the drawings are for the purpose of describing selected versions of the present invention and are not intended to limit the scope of the present invention.

As can be seen in FIG. 1, the present invention is a system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle. The present invention comprises a semi-automatic rifle 1 and a retrofit trigger actuating mechanism. The retrofit trigger actuating mechanism is integrated into the semi-automatic rifle 1. The present invention allows the user to increase the firing rate of a standard semi-automatic firearm through a minor modification. The method with which the present invention increases the firing rate of a semi-automatic firearm is also known as bump fire. The bump fire method utilizes the recoil motion of the gun to re-set and subsequently pull the trigger 3 sin continuous fashion, thus decreasing the amount of time between firing. The retrofit trigger actuating mechanism comprises an upper guide bracket 12, a lower finger guide bracket 17, and a lever arm 25. The lower finger guide bracket 17 allows the user to place his or her finger in a comfortable rest state on the trigger 3 of the rifle while the rest of the rifle moves backwards and forwards continuously. The lever arm 25 pivotably couples the lower finger guide bracket 17 to the stock 9 of the rifle. The upper guide bracket 12 is slidably engaged to the lower finger guide bracket 17. The integration of the retrofit trigger actuating mechanism into the semi-automatic rifle 1 essentially divides the semi-automatic rifle 1 into two separate regions, the front region and the rear region, that are capable of moving relative to each other. This relative motion between the front region and the rear region allows for the user to utilize the bump fire technique efficiently and accurately.

The retrofit trigger actuating mechanism may be modified and adapted to accommodate different types of firearms such as, but are not limited to, the AR-10, HK-91, and other similar firearms. The semi-automatic rifle 1 comprises a stock buffer 8, a stock 9, a handle grip 7, and a lower receiver region 2. The stock buffer 8 is attached adjacent to the lower receiver region 2 per standard design. The stock 9 is slidably mounted onto the stock buffer 8 as seen in FIG. 2. In the preferred embodiment, the stock 9 is a standard six position collapsible component. Set in the correct setting, the stock 9 allows the stock buffer 8, and the associated components connected to the stock buffer 8, to move relative to the stock 9. The user holds, orients, and aims the firearm through the use of a handle grip 7; the handle grip 7 is used by the firing hand. A variety of handle grips 7 may be utilized with the present invention; the ideal handle grip 7 contains a plurality of soft contoured regions about the outer surface to provide the user with comfort and increased friction; stabilizing the semi-automatic rifle 1 and therefore increasing the accuracy of the firearm.

The lower receiver region 2 comprises a trigger 3, a trigger guard 4, and a grip mounting bracket 5. The components of the semi-automatic firearm are essential to the function of the present invention. The trigger 3 is the mechanism that actuates the firing mechanism of the semi-automatic rifle 1. Surrounding the trigger 3 is the trigger guard 4; the trigger guard 4 protects the user's finger as well as prevents accidental actuation of the trigger 3. The grip mounting bracket 5 allows for the attachment of a handle grip 7 and as such the grip mounting bracket 5 is positioned adjacent to the trigger guard 4, opposite the trigger 3.

During operation the user grasps the handle grip 7, shoulders the stock 9, stabilizes the firearm with the offhand via hand guard or secondary handle grip, and rests the firing finger on the lower finger guide bracket 17. The lower finger guide bracket 17 situates the firing finger directly in front of the trigger 3. To initiate the bump fire technique, the user utilizes the offhand to push the front region forward, which includes the trigger 3, so the finger engages the trigger 3 and initiating the firing mechanism. The recoil from the discharge will force the front region to move longitudinally backwards towards the user, simultaneously disengaging the trigger 3 from the firing finger and subsequently re-setting the firing mechanism. To continue firing, the user then pushes the front region forward once again and forces the trigger 3 to collide with the firing finger and thus repeating the cycle; this cycle can be repeated as long the user chooses. During these steps the rear region stays at rest engaged with the user's shoulder and firing hand. Additionally, to help aid in the forward motion of the front region, after each recoil, a spring is placed in between the two regions.

The upper guide bracket 12 acts as the adapter for the semi-automatic rifle 1 and as such allows the rest of the components of the retrofit actuating mechanism to slidably attach the semi-automatic rifle 1; the upper guide bracket 12 rigidly mounts to the lower receiver region 2. The upper guide bracket 12 comprises a bracket body 13, a mount receiving slot 14, and an at least one first track component 15. In the preferred embodiment, the bracket body 13 comprises a rectangular shaped extrusion of a certain length with the lower right side is chamfered to a certain degree; in addition the rear vertical edges are rounded as seen in FIG. 8. The mount receiving slot 14 traverses into the bracket body 13 as seen in FIG. 8. In the preferred embodiment, the mount receiving slot 14 is shaped complimentary to the grip mounting bracket 5 of the lower receiver region 2 of the rifle to facilitate a snug fit. The upper guide bracket 12 is mounted onto the grip mounting bracket 5 with the grip mounting bracket 5 being attached into the mount receiving slot 14. In the preferred embodiment, the grip mounting bracket 5 and the upper guide bracket 12 both contain a hole that are coincidentally aligned when the two components are coupled as described above. A screw is then used to rigidly engage the upper guide bracket 12 and the grip mounting bracket 5. Other alternative means for attaching the upper guide bracket 12 and the grip mounting bracket 5 may also be utilized. The at least one first track component 15 is laterally positioned on the bracket body 13. The at least one first track component 15 is also positioned perpendicular to the mount receiving slot 14. In the preferred embodiment, the at least one first track component 15 comprises a first left track and a first right track. The first left track is rectangular recession that is on the left side of the bracket body 13; in a similar fashion the first right track is a rectangular recession that is on the right side of the bracket body 13. The length, width, and depth of the first left track and first right track are complimentary to the extrusions of an at least one second track component 18 of the lower finger guide bracket 17.

The lower finger guide bracket 17 comprises a left ear portion 19, a right ear portion 21, a stop portion 23, an at least second track component, and a grip attachment portion 24 as seen in FIG. 9. The left ear portion 19 and the right ear portion 21 are positioned parallel to each other and are offset from each other at a certain distance. The stop portion 23 is adjacently positioned in between the left ear portion 19 and the right ear portion 21; the stop portion 23 is also orientated in perpendicular manner to the left ear portion 19 and the right ear portion 21. The front surface of the stop portion 23 is shaped to the outer contours of the upper guide bracket 12 in a complimentary fashion, essentially a cavity specifically designed for the upper guide bracket 12 as seen in FIG. 9. During sequential firing, the stop portion 23 creates a buffer upon which the upper guide bracket 12 comes in contact with; this initiates the reciprocating movement necessary to initiate another firing sequence of the semi-automatic rifle 1. The left ear portion 19 and right ear portion 21 provide the user with a place to rest his or her trigger finger during the reciprocating motion of semi-automatic rifle 1. The left ear portion 19 and the right ear portion 21 each comprise a finger resting end 20; the finger resting end 20 of the left ear portion 19 is positioned opposite the stop portion 23; and in a similar fashion, the finger resting end 20 of the right ear portion 21 is positioned opposite the stop portion 23.

In one embodiment, the distance between the finger resting end 20 of the left ear portion 19 and the stop portion 23 is greater than the distance between the finger resting end 20 of the right ear portion 21 and the stop portion 23; this design is specialized for a user that use his or her right hand for pressing the trigger 3. In another embodiment, the distance between the finger resting end 20 of the left ear portion 19 and stop portion 23 is less than the distance between the finger resting end 20 of the right ear portion 21 and the stop portion 23; this design is specialized for a user that use his or her left hand for firing.

The offset distance between the finger end rests of the left ear portion 19 and the right ear portion 21 allow the user's firing finger to relax comfortably during the reciprocating motion of the semi-automatic rifle 1; the offset provides support for the distal and middle phalanx regions of the firing finger. In yet another embodiment, the distance between the finger resting end 20 of the left ear portion 19 and stop portion 23 is equal to the distance between the finger resting end 20 of the right ear portion 21 and the stop portion 23; this is an ambidextrous design.

In relation to the semi-automatic rifle 1, the left ear portion 19 is positioned adjacent to both the trigger 3 and the trigger guard 4 as seen in FIG. 1. In a similar fashion, the right ear portion 21 is positioned adjacent to both the trigger 3 and the trigger guard 4, opposite the left ear portion 19. Because the left ear portion 19 and the right ear portion 21 are positioned on either side of the trigger 3, when the user places his firing finger on the lower finger guide bracket 17 the finger will engage the trigger 3; or, at least place his or her finger in the path of the trigger 3 when relative motion occurs.

The grip attachment portion 24 is integrated adjacent to the left ear portion 19, the right ear portion 21, and the stop portion 23. The grip attachment portion 24 allows the user to attach a grip handle to the apparatus and as such is located towards the lower region of the component. In the preferred embodiment, the grip attachment portion 24 is underneath the stop portion 23 and is partially angled so as the handle grip 7 is partially angled similar to traditional firearm designs.

In relation to the semi-automatic rifle 1, the handle grip 7 is mounted adjacent and onto the grip attachment portion 24, opposite the upper guide bracket 12. Attachment means between the grip attachment portion 24 and the handle grip 7 include, but are not limited to, screws, bolts, adhesive, welding, and other comparable coupling mechanisms. In the preferred embodiment, the grip attachment portion 24 contains a threaded hole which aligns with the mounting hole 10 of standard grip handle designs; a screw is then used to attach the handle grip 7 and the grip attachment portion 24 in a rigid fashion.

The at least one second track component 18 is positioned parallel to the length of the left ear portion 19 and the right ear portion 21. In the preferred embodiment, the at least one second track component 18 comprises a second left track and a second right track. The second left track is a rectangular extrusion that is on the inner surface of the left ear portion 19; in a similar fashion the second right track is a rectangular extrusion that is on the inner surface of the right ear portion 21. The second left track and the second right track span a certain length of the left ear portion 19 and right ear portion 21. The depth, width, and design of the second left track and second right track are complimentary to the first left track and first right track.

In alternative embodiments, the at least one first track component 15 is a first single track that is located on either the left or right side of the bracket body 13. In said embodiments the at least one second track component 18 is a second single track that is located on the complimentary side as the first single track.

The upper guide bracket 12 is slidably situated in between the left ear portion 19 and the right ear portion 21 through the slidable engagement between the at least one first track component 15 and the at least one second track component 18. This design allows for the lower finger guide bracket 17, handle grip 7, lever arm 25, and the stock 9 move relative to the upper guide bracket 12, the lower receiver region 2 and the rest of the semi-automatic rifle 1. In different embodiments, various alternative means for slidably engaging the upper guide bracket 12 and the lower finger guide bracket 17 may be utilized, including but not limited to wheels, bearings, and or alternative track systems. The relative movement is characterized by back and forth oscillating motion. Relative longitudinal oscillation of the two groups of components listed above result in the trigger 3 being pulled and re-set a plurality of times in a sequential manner yielding a higher firing rate when compared to traditional semi-automatic firearms.

In the preferred embodiment, the lever arm 25 further comprises a fixed end portion 26 and a pivotal attachment end 27. The fixed end portion 26 is connected adjacent to the stop portion 23, opposite to both the left ear portion 19 and the right ear portion 21. The pivotal attachment end 27 is pivotably attached to the stock 9. The fixed end portion 26 comprises a channel portion 28, a pinhole 29, a pivot pin 30, and a sling adapter 31. The channel portion 28 is designed to resemble a U-shape when viewed from the top perspective as seen in FIG. 9 and dimensioned to mount onto the stock 9 of the rifle as seen in FIG. 3. The pinhole 29 traverses through the channel portion 28, perpendicular to the length of the lever arm 25. The pivot pin 30 is used to couple the lever arm 25 to the stock 9 of the rifle. The sling adapter 31 allows the user to use a sling with the rifle.

In the preferred embodiment, the stock 9 further comprises a mounting hole 10 that is used to attach the pivotal attachment end 27. The mounting hole 10 is located towards the front of the stock 9 and traverses through the stock 9 perpendicular to the length of the stock 9 as seen in FIG. 2. The preferred attachment means utilizes the pivot pin 30 of the lever arm 25 and through the following constraints; the mounting hole 10 is positioned into the channel portion 28 with the pinhole 29 concentrically aligned with the mounting hole 10; and, the pivot pit 30 traverses through the pinhole 29 and the mounting hole 10 as seen in FIG. 2. Additionally, the sling adapter 31 is laterally positioned to the stock 9 and pivotably attached adjacent to the pivot pin 30.

In alternative embodiments, the semi-automatic rifle 1 design uses a selector spring in conjunction with a selector detent to allow the user to put the firearm into various firing modes in order to prevent accidental firing and vary the amount of shots fired per instance. In said embodiments, the upper guide bracket 12 further comprises a selector spring hole 16. The selector spring hole 16 traverses through the bracket body 13, adjacent to the mount receiving slot 14. The selector spring hole 16 is characterized by certain diameter and distance. Additionally, the selector spring hole 16 is positioned parallel to the mount receiving slot 14. The selector spring hole 16 functions as the receptive cavity for the selector spring which in turn allows for firing state selection. The semi-automatic rifle 1 further comprises a selector detent spring hole 6 that is located on the lower receiver. When the upper guide bracket 12 is attached to the lower receiver region 2, as described above, the selector spring hole 16 is coincidentally aligned with the selector detent spring hole 6, allowing for the selector spring and detent to be aligned within.

In the preferred embodiment, to help further facilitate the bump fire technique the retrofit actuating mechanism further comprises a spring 32. Additionally, the stock 9 comprises a buffer-receiving cavity 11. The spring 32 is concentrically positioned within the buffer-receiving cavity 11; and, the stock buffer 8 traverses into the buffer-receiving cavity 11, pressing against the spring 32. The spring 32 is compressed between the stock buffer 8 and the stock 9, a configuration which continuously pushes the stock 9, stock buffer 8, and the associated components away from each other. The spring 32 helps to push the front region forwards after each recoil.

Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

What is claimed is:
 1. A system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle comprises: an upper guide bracket; a lower finger guide bracket; a lever arm; the lower finger guide bracket comprises a left ear portion, a right ear portion, a stop portion, and a grip attachment portion; the lever arm comprises a fixed end and a pivotal attachment end; the left ear portion and the right ear portion being offset from each other; the left ear portion and the right ear portion being positioned parallel to each other; the stop portion being positioned perpendicular to the left ear portion and the right ear portion; the stop portion being positioned in between the left ear portion and the right ear portion; the stop portion being connected adjacent to both the left ear portion and the right ear portion; the grip attachment portion being integrated adjacent to the left ear portion, the right ear portion, and the stop portion; the fixed end being connected adjacent to the stop portion, opposite to both the left ear portion and the right ear portion; and the upper guide bracket being slidably situated in between the left ear portion and the right ear portion.
 2. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 1 comprises: the left ear portion and the right ear portion each comprise a finger resting end; the finger resting end of the left ear portion being positioned opposite stop portion; and the finger resting end of the right ear portion being positioned opposite stop portion.
 3. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 2 comprises: a distance between the finger resting end of the left ear portion and the stop portion being greater than a distance between the finger resting end of the right ear portion and the stop portion.
 4. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 2 comprises: a distance between the finger resting end of the left ear portion and the stop portion being less than a distance between the finger resting end of the right ear portion and the stop portion.
 5. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 2 comprises: a distance between the finger resting end of the left ear portion and the stop portion being equal to a distance between the finger resting end of the right ear portion and the stop portion.
 6. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 1 comprises: the upper guide bracket comprises a bracket body, a mount receiving slot, an at least one first track component, and a selector spring hole; the mount receiving slot traversing into the bracket body; the at least one first track component being laterally positioned on the bracket body; and the at least one first track component being positioned perpendicular to the mount receiving slot.
 7. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 6 comprises: the selector spring hole traversing into the bracket body adjacent to the mount receiving slot; and the selector spring hole being positioned parallel to the mount receiving slot.
 8. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 1 comprises: the pivotal attachment end comprises a channel portion, a pinhole, a pivot pin, and a sling adapter; the pinhole traversing through the channel portion; the pinhole being perpendicular to the length of the lever arm; the pivot pin being situated within the pinhole; and the sling adapter being pivotably attached adjacent to the pivot pin.
 9. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 1 comprises: the lower finger guide bracket further comprises at least one second track component; the at least one second track component being positioned parallel to a length of the left ear portion and the right ear portion; and the at least one second track component being slidably engaged to an at least one first track component of the upper guide bracket.
 10. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 1 comprises: a semi-automatic rifle; the semi-automatic rifle comprises a lower receiver region, a handle grip, a stock buffer, and a stock; the stock buffer being attached adjacent to the lower receiver region; the stock being slidably mounted onto the stock buffer; the lower receiver region comprises a trigger, a trigger guard, and a grip mounting bracket; the upper guide bracket being mounted onto the grip mounting bracket; the left ear portion being positioned adjacent to both the trigger and the trigger guard; the right ear portion being positioned adjacent to both the trigger and the trigger guard, opposite the left ear portion; the handle grip being mounted adjacent and onto the grip attachment portion, opposite to the upper guide bracket; and the pivotal attachment end being pivotally attached to the stock.
 11. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 10 comprises: the lower receiver region further comprises a selector detent spring hole; the upper guide bracket comprises a bracket body, a mount receiving slot, and a selector spring hole; the trigger being surrounded by the trigger guard; the grip mounting bracket being attached into the mount receiving slot; the bracket body being positioned adjacent to the trigger guard, opposite the trigger; and the selector spring hole being positioned coincident to the selector detent spring hole.
 12. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 10 comprises: the stock comprises a mounting hole the pivotal attachment end comprises a channel portion, a pinhole, a pivot pin, and a sling adapter; the mounting hole being positioned into the channel portion; the pinhole being concentrically positioned with the mounting hole; the pivot pin traversing through the pinhole and the mounting hole; and the sling adapted being laterally positioned to the stock.
 13. The system for a retrofit trigger actuating mechanism integrated into a semi-automatic rifle as claimed in claim 10 comprises: the retrofit trigger actuating mechanism further comprises a spring; the stock comprises a buffer-receiving cavity; the spring being concentrically positioned within the buffer-receiving cavity; the stock buffer traversing into the buffer-receiving cavity; and the stock buffer being pressed against the spring. 